Interpersonal expectancy effects are less thoroughly understood in children than in adults, yet they can have practical implications for children's interactions. To understand better children's expectancies, this study extended earlier work to include expectancies of adults, preexisting (i.e., noninduced) expectancies, and joint effects of expectancies and subsequent perceptions. Children (N = 81) in Grades 4 through 6 (i.e., 9- to 12-year-olds) indicated their expectancies of adults who subsequently interacted with them using a style of either autonomy support (AS) or control (CN). After each interaction, children reported on perceived AS and on rapport. Results indicated that children's expectancies and subsequent perceptions interact to predict rapport, adult AS is associated with increased rapport, and the effect of children's expectancies on rapport is only partially mediated by their perceptions.